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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                        ________________________________

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

                                  March 3, 2005

                Date of Report (Date of earliest event reported)
                        ________________________________

                              SONUS NETWORKS, INC.
             (Exact Name of Registrant as Specified in its Charter)



         DELAWARE                  000-30229                 04-3387074
         --------                  ---------                 ----------
 (State or Other Jurisdiction     (Commission              (IRS Employer
      of Incorporation)           File Number)            Identification No.)

                250 APOLLO DRIVE, CHELMSFORD, MASSACHUSETTS 01824
               (Address of Principal Executive Offices) (Zip Code)

                                 (978) 614-8100

              (Registrant's telephone number, including area code)

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Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

   |_|  Written communications pursuant to Rule 425 under the Securities Act (17
CFR 230.425)
   |_|  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
CFR 240.14a-12)
   |_|  Pre-commencement communications pursuant to Rule 14d-2(b) under the
Exchange Act (17 CFR 240.14d-2(b))
   |_|  Pre-commencement communications pursuant to Rule 13e-4(c) under the
Exchange Act (17 CFR 240.13e-4(c))


Item 2.02. Results of Operations and Financial Condition. The information in this Current Report on Form 8-K and the exhibits attached hereto shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing. On March 3, 2005, Sonus Networks, Inc. issued a press release reporting its preliminary financial results for the quarter ended December 31, 2004. A copy of the press release is attached as Exhibit 99.1 hereto. Item 9.01. Financial Statements and Exhibits. (c) Exhibits The following exhibit relating to Item 2.02 shall be deemed to be furnished, and not filed: 99.1 Press release of Sonus Networks, Inc. dated March 3, 2005 reporting preliminary financial results for the quarter ended December 31, 2004.

SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Date: March 3, 2005 SONUS NETWORKS, INC. By: /s/ Ellen Richstone ----------------------- Ellen Richstone Chief Financial Officer

Exhibit Index 99.1 Press release of Sonus Networks, Inc. dated March 3, 2005 reporting preliminary financial results for the quarter ended December 31, 2004.

                                                                    Exhibit 99.1

Sonus Networks Announces Preliminary 2004 Fourth Quarter Financial Results

    CHELMSFORD, Mass.--(BUSINESS WIRE)--March 3, 2005--Sonus Networks
(Nasdaq:SONS), a leading supplier of service provider voice over IP
(VoIP) infrastructure solutions, today reported its preliminary
financial results for its fourth quarter of the fiscal year ended
December 31, 2004.
    Sonus expects to report for the fourth quarter of fiscal 2004
revenues of between $43 million - $46 million and earnings of between
$0.02 - $0.03 per diluted share. The company generated positive cash
flow in the fourth quarter and ended the year with $313 million in
cash, cash equivalents and marketable securities.
    The company has determined to wait to report its full financial
results until the completion of the audit of its financial statements
and the filing of its Annual Report on Form 10-K. The company has been
working diligently to complete its fiscal 2004 audited financial
results and its internal controls assessment and testing as required
by Section 404 of Sarbanes-Oxley. While the company has made
considerable progress, it does not expect to have final, audited
financial results until it files its Form 10-K. In light of previously
reported material weaknesses in its internal control over financial
reporting, the company believes it is prudent to report its full
financial results after its audit has been completed and it files its
audited financial statements. The preliminary results reported in this
release may be subject to change in connection with the completion of
the company's audited financial statements. While there can be no
assurances it will do so, the company expects to timely file its Form
10-K by March 16, 2005.
    "Sonus made important advances in many dimensions of our business
in 2004," said Hassan Ahmed, chairman and CEO, Sonus Networks. "During
the year, we expanded our customer base with new deployments at some
of the world's most dynamic service providers, including SOFTBANK BB
Corp, AT&T Corporation and AT&T Wireless. We launched important
channel relationships with industry leaders, Motorola, Marconi and
China Putian. Finally, we expect to be profitable on an annual basis
and generated positive cash flow, ending the year with a strong
balance sheet. When Sonus reports its complete financial statements
for the fourth quarter and year end, we look forward to providing more
detail on our progress during the fourth quarter."

    Sarbanes-Oxley Update

    In connection with the company's 2004 year-end financial review,
the company has been assessing and testing its internal control over
financial reporting, as required by Section 404 of Sarbanes-Oxley.
Based on its assessment and testing, company management will conclude
that there were material weaknesses in Sonus' internal control over
financial reporting as of December 31, 2004. Management's assessment
of Sonus' internal control will be included in the company's Form
10-K.

    Conference Call and Webcast Information

    Sonus Networks will host a conference call today, March 03, 2005,
beginning at 4:45 p.m. Eastern time. To listen via telephone, the
dial-in number is (888) 882-0115 or (415) 537-1985. Sonus will also
host a live webcast of the conference call. To access the webcast,
visit www.sonusnet.com, Corporate, Investor Relations. A telephone
playback of the call will be available following the conference and
can be accessed by calling (800) 633-8284 or (402) 977-9140. The
reservation number for the replay is 21228369. The telephone playback
will be available through Thursday, March 17, 2005. The webcast will
be also available on the Sonus Networks Investor Relations site
through Friday, March 03, 2006. To access the replay of the webcast,
visit www.sonusnet.com (http://www.sonusnet.com), Corporate, Investor
Relations.

    About Sonus Networks

    Sonus Networks, Inc. is a leading provider of voice over IP (VoIP)
infrastructure solutions for wireline and wireless service providers.
With its Open Services Architecture (OSA), Sonus delivers end-to-end
solutions addressing a full range of carrier applications, including
trunking and tandem switching, residential and business access,
network border switching and enhanced services. Sonus' voice
infrastructure solutions, including media gateways, softswitches and
network management systems, are deployed in service provider networks
worldwide. Sonus, founded in 1997, is headquartered in Chelmsford,
Massachusetts. Additional information on Sonus is available at
http://www.sonusnet.com.

    This release may contain forward-looking statements regarding
future events that involve risks and uncertainties. Readers are
cautioned that these forward-looking statements are only predictions
and may differ materially from actual future events or results.
Readers are referred to the "Risk Factors" section of Sonus' Annual
Report on Form 10-K/A dated July 28, 2004 and filed with the SEC, and
the "Cautionary Statements" section of Sonus' Quarterly Report on Form
10-Q, dated November 9, 2004 and filed with the SEC, which identify
important risk factors that could cause actual results to differ from
those contained in the forward-looking statements. In addition, Sonus'
financial results are not considered final until the filing of the
company's annual report on Form 10-K with the SEC and there can be no
assurance that the company will timely file its Form 10-K. Any
forward-looking statements represent Sonus' views only as of today and
should not be relied upon as representing Sonus' views as of any
subsequent date. While Sonus may elect to update forward-looking
statements at some point, Sonus specifically disclaims any obligation
to do so.
    Sonus is a registered trademark of Sonus Networks. Open Services
Architecture, GSX9000, Insignus and Sonus Insight are trademarks of
Sonus Networks. All other trademarks, service marks, registered
trademarks, or registered service marks are the property of their
respective owners.

    CONTACT: Investor Relations:
             Sonus Networks
             Jocelyn Philbrook, 978-589-8672
             jphilbrook@sonusnet.com
                 or
             Media Relations:
             Laureen McGowan, 617-275-6515
             lmcgowan@greenoughcom.com